получить пароль (get a password)
Имя (Name)
getpass - get a password
Синопсис (Synopsis)
#include <unistd.h>
char *getpass(const char *prompt);
Feature Test Macro Requirements for glibc (see
feature_test_macros(7)):
getpass():
Since glibc 2.2.2:
_XOPEN_SOURCE && ! (_POSIX_C_SOURCE >= 200112L)
|| /* Glibc since 2.19: */ _DEFAULT_SOURCE
|| /* Glibc <= 2.19: */ _BSD_SOURCE
Before glibc 2.2.2:
none
Описание (Description)
This function is obsolete. Do not use it. If you want to read
input without terminal echoing enabled, see the description of
the ECHO flag in termios(3).
The getpass() function opens /dev/tty (the controlling terminal
of the process), outputs the string prompt, turns off echoing,
reads one line (the "password"), restores the terminal state and
closes /dev/tty again.
Возвращаемое значение (Return value)
The function getpass() returns a pointer to a static buffer
containing (the first PASS_MAX bytes of) the password without the
trailing newline, terminated by a null byte ('\0'). This buffer
may be overwritten by a following call. On error, the terminal
state is restored, errno is set to indicate the error, and NULL
is returned.
Ошибки (Error)
ENXIO The process does not have a controlling terminal.
Файлы (Files)
/dev/tty
Атрибуты (Attributes)
For an explanation of the terms used in this section, see
attributes(7).
┌───────────────────────────────┬───────────────┬────────────────┐
│Interface │ Attribute │ Value │
├───────────────────────────────┼───────────────┼────────────────┤
│getpass() │ Thread safety │ MT-Unsafe term │
└───────────────────────────────┴───────────────┴────────────────┘
Стандарты (Conforming to)
Present in SUSv2, but marked LEGACY. Removed in POSIX.1-2001.
Примечание (Note)
In the GNU C library implementation, if /dev/tty cannot be
opened, the prompt is written to stderr and the password is read
from stdin. There is no limit on the length of the password.
Line editing is not disabled.
According to SUSv2, the value of PASS_MAX must be defined in
<limits.h> in case it is smaller than 8, and can in any case be
obtained using sysconf(_SC_PASS_MAX). However, POSIX.2 withdraws
the constants PASS_MAX and _SC_PASS_MAX, and the function
getpass(). The glibc version accepts _SC_PASS_MAX and returns
BUFSIZ (e.g., 8192).
Ошибки (баги) (Bugs)
The calling process should zero the password as soon as possible
to avoid leaving the cleartext password visible in the process's
address space.
Смотри также (See also)
crypt(3)
